The present invention relates to an apparatus for thermalizing or cooking food in an oven, using an evaporator to maintain the desired difference between the wet bulb and dry bulb temperatures in the food chamber.
Traditional ovens characteristically utilize a dry heat system. The limitations of this equipment have led users to develop alternate cooking techniques, such as papillote cooking (bag cooking) in an effort to have some control over the parameters which actually affect the quality of the end product. Winston Industries has manufactured ovens or thermalizers having evaporators, in which the temperature of water in the evaporator was controlled, and these ovens have provided a much improved ability to control the quality of the food.
The present invention provides an oven in which the evaporator is conveniently located on the access door to the oven. This facilitates the task of adding water to the evaporator, checking the water level in the evaporator, and draining the water from the evaporator.
An embodiment of the present invention also adds a control feature which allows the water in the evaporator to be brought up to boiling temperature to prevent bacteria build-up.
An embodiment of the present invention also adds a sparger, which injects air into the evaporator in order to enhance the transfer of moisture from the evaporator to the food chamber.
In a preferred embodiment, the cook has three settings he can control. First, he sets the wet bulb temperature inside the food chamber, which establishes the ultimate food temperature. The controller controls this temperature by controlling a heater inside an evaporator. Second, the cook sets the degree of browning of the food, which really is setting a differential between the wet bulb temperature and the dry bulb temperature in the food chamber. The control system controls the difference between the dry-bulb-temperature and the wet-bulb-temperature in the food chamber (thereby controlling the degree of browning) by controlling a heater that heats the air in the food chamber. Temperature sensors in both the evaporator and in the food chamber provide feedback to the controller. Third, the cook may set a timer.
The food itself, inside the food chamber, acts like a wet bulb sensor, since is it has a moist outer surface and is sensing the conditions inside the oven. The temperature in the evaporator establishes the wet bulb temperature in the food chamber, which, in turn, establishes the final food temperature. This means that the temperature sensor in the evaporator senses a temperature that is very close to the final temperature of the food. By being able to control the difference between the wet bulb temperature and the dry bulb temperature inside the food chamber (thereby controlling the driving force that causes evaporation of moisture from the food), the cook can control the browning of the food.
Thus, this oven gives the cook a superior ability to control the quality of food and to reproduce that quality on a regular basis.